Control Nature the Natural Way

Horticulture Hotline 07/27/15

  Bill Lamson-Scribner

Biopesticides (also called bioscience products) are pesticides that are found in nature. Do you remember studying how the black walnut tree exudes its own preemergent herbicide (juglone that causes an allelopathic effect) to keep other plant life from growing underneath it and competing with it?  This is definitely the way of the future! 

The most common biopesticides that you might have heard of in the past would be pheromone traps for catching flies or Japanese beetles.  Pheromones are a natural chemical attractants (usually sexual) that animals as well as insects produce. You put these attractants on a glue board to attract flies and Japanese beetles and they get stuck. Bt or Bacillus thuringiensis is a bacteria that controls many different worms, caterpillars, mosquito larvae or Lepidoptera insects.  Diatomaceous earth is a natural contact insecticide derived from microscopic plankton or algae with silica skeletons.  Roaches, ants, fleas, and snails walk across this product and it causes abrasions to their exoskeleton and they dry out and die.

Many of the major chemical manufacturers are spending more money developing these types of products (finally) because they are easier to get approved through the EPA, saving them money in the long run.

Most bioscience products are very specific to certain pests.  In some cases it is required that you use them more frequently because the product breaks down in the environment very quickly.  Diatomaceous earth on the other hand lasts a very long time. It is important that you know the life cycle of the insect or pest that you are after because some bioscience products only attack the pests at a certain stage in their life cycle. 

Some bioscience products that we had had a lot of success with include; Harpin protein, Neem Oil, Spinosad, beneficial nematodes, various oils and insecticidal soaps.  Other bioscience products called bionutritional products or biostimulants that we have seen great success with include; humic acid (Possum Hume), seaweed products (liquefied seaweed and sea kelp products), and amino acid products.  SeaHume (a combination or seaweed and humic acid) is a proven performer in the Lowcountry.

To give you an example of a bioscience product, Harpin protein (found in Mighty Plant) is a bacteria’s (fire blight) waste product (poop) that is sprayed on the plant.  The plant thinks it is being attacked by a bacteria so it goes into its defensive mode.  The plant’s cuticle thickens preventing attack from certain insects, fungi and bacteria.  This cuticle thickening also conserves water.  The plant also flowers profusely in an effort to create seeds to perpetuate its species (war time babies) and also grows a larger root system.  Since most people grow plants for flowers, this is an obvious benefit.  A plant that has been treated with Harpin protein is more drought tolerant, has better flowers, has better foliage, can resist certain fungus and insect attacks, and has a stronger root system than an untreated plant. 

Always read, understand and follow product label. The product label is a Federal Law.

Sod

I have been getting a lot of questions about laying new sod this year. Here is a basic outline. You may want to consult with a professional as sod is expensive and tricky to get just right. This outline is for someone that wants to control weeds before sodding (start clean stay clean) not for the person that has a wedding in their back yard in 3 days!

                                                                                   

NEW GRASS

                                                                                                                                   MONTH     WEEK (COULD START ANYTIME APRIL - AUGUST)  PRODUCT 

START                                  TAKE SOIL TEST

                                               SPRAY SLOW ACTING GLYPHOSATE                                

START + 2 WEEKS                TILL         ADD AMENDMENTS

                                                SEAHUME                                         15#/M

                                                COTTON BURR ADD 3’’ TO TOP TILL IN 4-8 INCHES

                                          

START + 4 WEEKS                   SPRAY BURN DOWN PRODUCT                 

                                                                      OR

                                                 SPRAY SLOW ACTING GLYPHOSATE

IF YOU USE SLOW ACTING GLY WAIT 2 WEEKS, IF FAST KILL PRODUCT FOLLOW LABEL

                                   ESTABLISH FINISH GRADE THEN ADD

                                   SUSTANE 04-04-04                                      25#/M

                                             SOD

                               WATER IN THEN ADD

                                             PERK                                                   10#/M

                                             DISARM                                                 3#/M

                                             SEVIN                                                     3#/M

                                WATER LIGHTLY AND OFTEN DEPENDING ON YOUR SITUATION AT FIRST, THEN BEGIN TO BACK OFF WATER AS GRASS ROOTS IN

2 WEEKS AFTER SOD      08-02-04                                                 6#/M

                                              SEAHUME                                            10#/M

                                              CLEARY’S                                            5#/M

                                              BIFEN                                                    4#/M

BEGIN MAINTENANCE PROGRAM BASED ON SOIL TEST

ALWAYS READ AND FOLLOW PRODUCT LABEL.

PLEASE MEASURE YOUR LAWN FOR ACCURATE APPLICATIONS. IT IS AGAINST FEDERAL LAW TO OVER APPLY PRODUCTS. ALSO IT CAN INJURE TURF, TREES, AND PLANTS.

POSSUM’S LANDSCAPE AND PEST CONTROL SUPPLY, LLC AND BILL LAMSON-SCRIBNER ASSUME NO LIABILITY WRITTEN OR IMPLIED.

THIS PROGGRAM IS JUST A GUIDE – SCOUT YOUR PROPERTY FOR POTENTIAL PROBLEMS.

FERTILIZERS WILL STAIN NON-TARGET AREAS (POOL DECKS, DRIVEWAYS, SIDEWALKS, ETC.) – ALWAYS APPLY WHEN DRY – BRUSH, SWEEP OR BLOW-OFF NON-TARGET AREAS – THEN WATER IN LAWN AREAS (UNLESS LABEL SAYS NOT TO WATER IN PRODUCT).

Bill Lamson-Scribner can be reached during the week at Possum’s Landscape and Pest Control Supply. Possum’s has three locations 481 Long Point Rd in Mt. Pleasant (971-9601), 3325 Business Circle in North Charleston (760-2600), or 606 Dupont Rd, in Charleston (766-1511). Bring your questions to a Possum’s location, or visit us at http://www.possumsupply.com. You can also call in your questions to “ The Garden Clinic”, Saturdays from noon to 1:00, on 1250 WTMA  (The Big Talker). The Horticulture Hotline is available 24 / 7 at possumsupply.com. 

Summer Time Disease

Between pop up thunderstorms, people going on vacation, and people just not mowing enough, gray leaf spot has exploded on St. Augustine grass.

Gray leaf spot (Pyricularia grisea) goes with St. Augustine like grits go with shrimp! Or like chinch bugs go with St. Augustine! To battle gray leaf spot you are best employing many cultural practices and using limited control products if necessary.

Gray leaf spot looks like someone burned or dripped acid on the leaves of the plant.  There are little oblong spots on the leaf.  Eventually, these spots grow together and the leaf blade dies.  Whole areas of your grass can disappear at once when these leaf blades die.

Culturally there are several things to do to minimize your problem with gray leaf spot.  This disease likes high humidity and excessive nitrogen fertilizer.  To help alleviate the high humidity, mow your grass to a level that seems abnormal to St. Augustine.  Try to get it down to 2 ½ - 3 inches depending on the variety of St. Augustine grass.  Also try to mow every 3 – 5 days with a bagger.  This mowing will help get sunlight down to the crown of the plant, drying the leaf blades as quickly as possible.

Mowing is always hard to get someone to modify the frequency of cuts. “The landscaper only comes every 7 or 14 days”, is what I usually hear. If you don’t want to cut it yourself in between visits by the landscaper (saving a trip to the gym and I have been told a cold beer is extra good after mowing), maybe you could hire a neighborhood kid or your kid to just mow the grass. No edging, blowing or weeding, just a quick mow.

Another alternative to you mowing is applying a growth regulator to your turf. These products work great at slowing your turf’s growth rate. Growth regulators are used extensively on golf courses and athletic fields. Growth regulators do a great job of managing your turf’s growth rate on your home lawn as well.

This fungus like most fungi likes hot humid weather.  Minimize the amount you water as much as possible.  Wait until your lawn is getting a blue/green color and your foot prints stay in the lawn after you walk across it before you water. Unfortunately, you can not control rainfall as easily. In the Lowcountry, afternoon thunderstorms are a way of life, so keep the grass mowed as low as you can so it will dry out quickly. 

Hold off of the nitrogen fertilizer until you can get this disease under control.  If you need some color, you could add a product like Possum’s Minors to give you some green without all the nitrogen. Watch starving your grass because a malnourished yard is more susceptible to disease. Very low rates of an organic fertilizer or cotton burr compost might help it recover.

At Possum’s, I know we have had several customers that swear they control this disease by using our wetting agent with biostimulants, cotton burr compost, and / or SeaHume along with the above cultural practices. 

If you have to resort to a control product, make sure the product is labeled for Pyricularia grisea.  There are many leaf spot diseases on labels of control products but only certain ones work on gray leaf spot on St. Augustine. We had one customer come in that had been applying a product that controlled Drechslera spp. and Biopolaris spp. leaf spot; however, the product was not labeled for Pyricularia grisea (watch where you shop). 

Honor Guard and Heritage are systemic products that you spray. Since this is a leaf spot fungus, the sprays seem to give good coverage over the leaf blade.  If you insist on a granular product, Prophesy (same active as Honor Guard and Banner), or Disarm are granular systemic products that are absorbed through the roots and will do a good job for you.